Integration of Chemosensory and Hormonal Stimuli

超出所提供的空间。雄性仓鼠和大多数哺乳动物一样，性腺类固醇激素是交配所必需的。阉割也会降低性动机，这可以通过对阴道气味的兴趣和对接受性的女性的偏好来衡量。然而，对类固醇刺激食欲性行为的机制的理解是有限的。这是拟议研究的总体目标。仓鼠是研究性动机的重要模型，因为交配依赖于化学感觉线索。雄性仓鼠在交配前会对雌性仓鼠进行广泛的肛门生殖器调查，切除嗅球会取消交配和对发情雌性的偏好。特定目标1中的研究将研究去势和类固醇替代对雌性仓鼠阴道分泌物（FHVS）检测和反应性的影响，以确定去势雄性是否可以检测FHVS，以及传递对FHVS反应性的类固醇信号。条件性味觉回避将用于评估化学感觉检测（目标1A），而目标1B和1C将使用FHVS的操作性反应评估化学感觉反应。具体目标2将确定化学感觉反应的激素控制的大脑通路。目的2A研究奖赏性化学感受信号在嗅粘膜和犁鼻器中的传递。目标2B和2C将集中于嗅球的中心目标。内侧视前区（MPOA）是表达完成性行为的关键。然而，MPOA的病变未能阻止对发情期女性的偏好，这表明其他大脑区域有助于类固醇对性动机的影响。内侧杏仁核（Me）是一个逻辑的网站在这方面。嗅球接受嗅球的传出，并有丰富的类固醇受体。我们已经证明，在我的睾丸激素刺激阉割男性的性活动。目的2B和2C将使用损伤和激素刺激来确定Me和MPOA在类固醇促进化学感觉反应性中的作用。这些研究有助于理解性动机，以及类固醇激素在食欲性行为中的意义。性能现场=

EXCEED THE SPACE PROVIDED. Gonadal steroid hormones are essential for mating in male hamsters, as in most mammals. Castration also reduces sexual motivation, as measured by interest in vaginal odors and preference for a receptive female. However, understanding of mechanisms for steroid stimulation of appetitive sexual behavior is limited. This is the overall objective of the proposed studies. Hamsters are an important model for investigating sexual motivation because mating is dependent on chemosensory cues. Male hamsters engage in extensive anogenital investigation of females before mating, and removal of the olfactory bulbs abolishes both copulation and preference for an estrous female. Studies in Specific Aim 1 will investigate the effects of castration and steroid replacement on detection of and responsiveness to female hamster vaginal secretion (FHVS) to determine if castrated males can detect FHVS, and the steroid signals that convey responsiveness to FHVS. Conditioned taste avoidance will be used to assess chemosensory detection (Aim 1A), while Aims 1B and 1C will evaluate chemosensory responsiveness using operant responding for FHVS. Specific Aim 2 will determine brain pathways for hormonal control of chemosensory responsiveness. Aim 2A will investigate the transduction of rewarding chemosensory cues in the olfactory mucosa and/or vomeronasal organ. Aims 2B and 2C will focus on central targets of the olfactory bulbs. The medial preoptic area (MPOA) is key to expression of consummatory sexual behavior. However, lesions of MPOA fail to prevent preference for an estrous female, suggesting that other brain regions contribute to steroidal effects on sexual motivation. The medial amygdaloid nucleus (Me) is a logical site in this regard. Me receives efferents from the olfactory bulbs, and has abundant steroid receptors. We have shown that testosterone in Me stimulates sexual activity in castrated males. Aims 2B and 2C will use lesions and hormone stimulation to determine the role of Me and MPOA in steroid facilitation of chemosensory responsiveness. These studies have relevance to understanding sexual motivation, and the significance of steroid hormones in appetitive sexual behavior. PERFORMANCE SITE ========================================Section End===========================================